John Walker developed a notation for labeling a class of circular orbit patterns called the Walker Delta Pattern (hereinafter “Walker”). This class has since become the standard. The Walker notation is i: T/P/F, where i is the inclination, T is the total number of spacecraft, P is the number of evenly spaced planes, and F determines the phase relationship between adjacent planes. The change in true anomaly, in degrees, for equivalent satellites in neighboring planes is equal to F*360/T. The Walker number is an integer between 0 and P-1. Walker constellations for continuous Earth observation typically use multiple satellites per plane, such that T and P are different integers, and almost always use an F value greater than zero.
A trivial example of a ring constellation is a number of spacecraft in essentially the same orbit, such as a constellation of communications and weather satellites at geostationary Earth orbit. Some embodiments of the present invention relate to a more complex arrangement of multiple satellites forming a ring structure across different orbits in different orbit planes. Thus, it may be beneficial to implement a ring constellation using one or more Walker patterns.